This invention relates generally to hydrocyclone assemblies such as are employed with fluid feeds for removing solid particulate material. More specifically, it relates to hydrocyclone assemblies suitable for application to high temperature fluid feeds.
Hydrocyclones are widely employed in various industries for separating operations. Thus they may be used for removal of undesired particular material from liquids, dewatering or concentrating operations, or for classification of solids. Many hydrocyclones are made of suitable metal with an inner liner made of material which resists erosion, such as a synthetic rubber or elastomer, or a ceramic material. For certain services, such as where the fluid feed is at an elevated temperature, the hydrocyclone may be made entirely of ceramic material. The mounting of such ceramic hydrocyclones has presented certain problems, particularly when one or more ceramic hydrocyclones are assembled within a pressure vessel. High temperatures (e.g., 700.degree. to 800.degree. F.) and rapid changes in temperature tend to cause development of leakage between the assembled parts, and localized stressing of the ceramic material to the point of causing breakage. Such temperatures and rapid temperature changes are experienced in the petroleum refining industry during the processing of certain petroleum products. A hydrocyclone failure during such processing operations may necessitate shutting down an entire processing system while making repairs.
Multicyclone assemblies as previously manufactured and sold by the assignee of this application, and certain assemblies made by others, have been subject to additional objectionable features. The upright cyclones of such assemblies are disposed between two vertically spaced plates, with the space between the plates forming a feed chamber into which the feed is introduced. The overflow and underflow materials discharge into the spaces above the upper and below the lower plate, respectively. The velocity of the incoming feed is relatively low with the result that solids tend to build up as a stagnant mass in the feed chamber. The accumulated solids may be of such character that they tend to compact and form agglomerates with the result that lumps may break off and plug the feed passages to the cyclone chambers, and what is more serious, may cause plugging of the cyclone underflow apex orifice or the overflow vortex finder.